I don't pretend to have all the answers, but what I've decided works for me personally is supporting a handful of hyper-focused charities that run very lean in terms of western staff and employ local skilled labour.
One example is the Canadian charity One4Another which performs surgeries to reverse some common birth defects in kids and babies in Uganda. They're not trying to feed the world, they're not interfering with the local economy; in fact they're employing doctors and nurses to perform a one-time intervention that changes the life of thousands of kids a year in the catchment area of their facility.
Obviously there are things that a group like this can't do but a massive NGO can, and that's great too, but for what I have to give, I feel very good about the impact per dollar of this.
OP is talking about corrupt officials, not charity workers, so how does "running lean" evade or obviate corruption?
Edit: my point is just that bribery and blackmail aren't the same as Global Northerners treating charities as synecures.
Yes, fair, maybe it doesn't. But I think several factors do work in favour of the smaller organization in terms of it being a smaller target, having the operation based more on local relationships and trust networks, and being accountable for an overall smaller budget— it's harder to ignore 10k in bribes of if it's only half a million or so per year coming in from the west.
Anyway as I say it's not everything but I thought it seemed relevant to the GP post talking about NGOs and charity efficiency.